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CEMENTS, LIMES, AND PLASTERS. 



all the drawing for the day being done in ten hours. Nut and slack 

 coal, mixed, are used for fuel. The fuel consumption amounts to about 

 30 Ibs. per barrel of cement, equivalent to 11.3 per cent on the weight 

 of the cement produced. 



At the Pembina plant in North Dakota a kiln 40 feet high and 10 feet 

 hi external diameter is used. The shell is of |-inch No. 14 boiler iron. 

 The klin space is broadest at the top, narrows about 6 feet down to a 



FIG. 40. Kilns of the Lawrence plant, Siegfried, Pa. 



throat about 6 feet in diameter, below which it again enlarges, reaching 

 almost to the kiln-shell at 15 feet above the base. Below this it is again 

 somewhat contracted to the drawing level. The kiln space is lined with 

 8-inch fire-brick and the space between these brick and the kiln-shell 

 Riled with ashes. This kiln produces about 50 barrels of 265 Ibs. 

 each per day, with a fuel consumption of one ton of Youghiogheny slack 

 Lignite slack, mixed half and half with Youghiogheny slack, has been used 





